Canadians were issued a new warning by Health Canada about a popular antioxidant touted for weight loss. Green tea extract is a concentrated form of green tea used in supplements, particularly weight loss products. Health Canada notes that the amount of green tea added to many drinks and foods would be safe to consume but that the extract, normally sold in pill, capsule or powder form has a higher concentrated form of Epigallocatechin gallate (EGCG), the ingredient at issue.
EGCG can be found in white and black teas in smaller amounts but is usually extracted from green tea and added to dietary supplements in forms that also include chewable products, gummies and tablets. Previous warnings had stated to “consult a health care practitioner prior to use if you have a liver disorder or develop symptoms of liver trouble…” but after a few reports worldwide and two in Canada, Health Canada this week added this Known Adverse Reaction: “Rare, unpredictable cases of liver injury associated with green tea extract-containing products have been reported (in Canada and internationally) (HC 2017).”
The American College of Gastroenterology noted in 2014 that green tea extract in very high doses could lead to liver damage, but it is not clear if lower doses of EGCG could lead to health problems. They also stated that it is unknown why one may develop a liver injury from green tea extract, although genetic susceptibility was suggested. Health claims for green tea extract are not allowed by the US FDA.
Health Canada recently reviewed reports of a link between EGCG and liver damage worldwide, including a few in Canada and decided an updated, stronger warning was required. Their caution for the ingredient now includes, “Stop use if you develop symptoms of liver trouble such as yellowing of the skin/eyes (jaundice), stomach pain, dark urine, sweating, nausea, unusual tiredness and/or loss of appetite and consult a health care practitioner.” They also now recommend that green tea extract should only be taken by adults over age 18.
Health Canada also stated they will require manufacturers to add these new additional warnings to their labels and information for products containing green tea extract.
